A. Yes and no, but mostly no. The backup application that comes with R2 is not officially supported for CSV. You can manually place the CSV in redirect access mode then back up the LUN on the coordinator node, but the Volume Shadow Copy Service (VSS) request wouldn't be sent to all nodes in the cluster, so not all virtual machines throughout the cluster would be notified to get their disk information in a backup-consistent state.

If you attempt to back up a CSV with Windows Backup, you'll see a warning in the event log (event 1584, shown here) that a backup application performed a VSS snapshot without properly preparing the volume (i.e. it didn't call the PrepareVolumeForSnapshotSet API function).

My advice is therefore to use a backup application that fully supports CSV, such as Data Protection Manager or a third-party backup application, to ensure the integrity and usability of your backups.

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